As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 391, BOS-TPA. DURING WALK AROUND FOUND INTER-GRANULAR CORROSION AT RT REAR FUSELAGE AT LAV EXHAUST; REF NR 440510-38011-REPAIRED IAW SRM 53-41-11-300-004 AND EC A18-475-01. THIS REPAIR HAS BEEN APPROVED PER THE REF/4/ RDAS. PER THE MAJOR/ MINOR CLASSIFICATION THIS REPAIR IS AS A “MAJOR”